1. Field of the Invention
The present invention relates to digging buckets for excavation vehicles and equipment such as front-end loaders and, more particularly, to a connection system for connecting replaceable teeth to such digging buckets.
2. Description of the Prior Art
Excavating buckets are used extensively in the construction and mining industries. The buckets are used with a variety of different excavating apparatus, such as backhoes, power shovels, front-end loaders, dragline equipment, etc., for digging, loading, etc. Although these buckets have many differences, they are generally formed with a rear wall, side walls, and a bottom wall. The walls cooperatively define an open front and a cavity for gathering earthen material and moving it to a dump site. The bottom edge of the open front is defined by a forward lip of the bottom wall. The lip is intended to engage the ground for collection of the earthen material into the bucket cavity. The lip may be formed to have a linear or arcuate-shaped edge or formed to have a particular configuration (such as V-shaped) to suit the desired operation. Similarly, the front edges of the side walls are also adapted to engage the ground.
Attachments are commonly mounted on the lip and front edges of the side walls to increase the effectiveness and durability of the buckets. These attachments typically include teeth, shrouds and wings. The teeth project forwardly of the lip to disrupt the material for enhanced collection of the material into the cavity. The shrouds are positioned in-between the teeth and are generally provided with an inclined surface to improve the collection of the material into the bucket. The wings are attached to the front edges of the side walls in general proximity with the lips. In any event, the attachments protect the bucket against undue wear. As a result, only the attachments normally need replacement when the front of the bucket becomes worn, thus prolonging the usable life of the larger and more expensive lip and side walls.
Generally, a tooth is attached to the lip with an adaptor. The tooth in turn is attached to the adaptor with a pin. In order to replace the tooth, the pin is knocked out with a large hammer. During this process, the pin is destroyed, which means that a new pin is needed to attach the new tooth to the adaptor. This is a non-desirable cost since pins typically cost in the range of $25.00-$50.00 each.
Furthermore, use of the large hammer to knock the pin out of the tooth-adaptor connection may be dangerous. There is a danger of injury to bodily parts, especially fingers, and also a danger from flying pieces or chips from the pin or other parts, or from dirt, debris, sand, dust, etc. in the connection area.
Another problem with current connection techniques lies in the fact that the interface between the tooth and its associated adaptor is not adequately sealed. Thus, dirt, sand, grit, and abrasives enter the interface between the tooth and adaptor and slowly grinds or wears the two parts. This wear loosens the tightness of the fit, and thus, new teeth may xe2x80x9cwigglexe2x80x9d and may be quickly damaged or broken. Due to this wear, it is necessary to relatively frequently replace the adaptor. Currently, a new adaptor is required for every 10-20 teeth that are installed on the associated adaptor. The frequency of the replacement of the adaptor depends on the amount of use, the type of soil, etc.
In its broadest sense, the present invention provides a connection system for connecting a first item and a second item, the first item including a receiving portion defined at least partially by an abutment wall and the second item including an interference portion, wherein the connection system comprises a biasing portion and a locking portion adjacent the biasing portion. The biasing portion is adjacent the abutment wall when the connection system is in use and includes at least one biasing pin protruding from a rear wall. The locking portion includes a locking section and an interference section that engages the interference portion when the connection system is in use. The locking section and the interference section are capable of movement relative to one another. The locking section includes at least one biasing plunger that engages a corresponding one of the at least one biasing pin when the connection system is in use.
In a preferred embodiment, a digging bucket assembly for an excavation apparatus that includes a bucket body having a lip running longitudinally along the bottom front portion of the bucket body has a plurality of adaptors connected thereto. Each adaptor includes a receiving portion defined therein that is at least partially defined by an abutment wall. The digging bucket further includes a corresponding plurality of teeth each connected to a respective adaptor with a connection system. Each tooth includes an interference portion. The connection system includes a biasing portion adjacent the abutment wall when the connection system is in use with the biasing portion including at least one biasing pin protruding from a rear wall. The connection system further includes a locking portion adjacent the biasing portion wherein the locking portion includes a locking section and an interference section that engages the interference portion when the connection system is in use. The locking section and interference section are capable of movement relative to one another. A locking section further includes at least one biasing plunger that engages a corresponding one of the at least one biasing pins when the connection system is in use.
In accordance with one aspect of the present invention, the locking section and the interference section are separate pieces that are adjacent one another.
In accordance with another aspect of the present invention, the locking section is connected to the biasing portion via a hinge.
In accordance with a further aspect of the present invention, the interference section and the locking section each include an angled surface that are adjacent one another.
In accordance with yet another aspect of the present invention, the biasing portion includes at least three biasing pins and the locking section includes at least three biasing plungers.
In accordance with a further aspect of the present invention, the interference portion comprises a notched find within the tooth and the interference section comprises a projection.
In accordance with yet another aspect of the present invention, the locking section includes an indentation defined within a top surface that engages an edge of the tooth.
Accordingly, the present invention provides a connection system that is ideally suited for connecting teeth of a digging bucket to adaptors located along a front lip of the digging bucket without the need for pins. The connection system is easy to fabricate and, since it preferably extends within the width of the receiving portion of the adaptor, no dirt can enter between the tooth and the portion of the adaptor over which it extends. The locking portion of the connection system fully engages the tooth and the adaptor with the interference section fully engaging the interference portion of the tooth, thus providing a tight fit and helping prevent relative motion between the tooth and its associated adaptor.
A connection system in accordance with the present invention is reusable and thus, pin replacement is eliminated, thereby saving money for each tooth replacement. Furthermore, a connection system in accordance with the present invention may be easily removed to replace its associated tooth and thus, there is no need for a hammer, thereby reducing the possibility of injuries when replacing teeth.
Other features and advantages of the present invention will be understood upon reading and understanding the detailed description of the preferred exemplary embodiments found herein below, in conjunction with reference to the drawings, in which like numerals represent like elements.